Schmitt trigger relaxation oscillator sim

Eyyyyy, finally got it (on both mine and your simulation - I had grabbed the original file not the updated)! Thank you so much!

You were once again correct the input and outputs were swapped. I could have sworn I tweaked that last night but I guess I didn’t (looking at the circuit first thing with coffee in hand definitely helps).

Lots of little things to keep track of. May I ask how you spotted the error?
Is part of the spice work flow just always checking the model file against the netlist to ensure that they match in order? Or do they have an explicit order?

From the model file:
From the netlist:
XU1 /out /cc /vdd 0 CD40106B

Should the above always be out in pwr gnd or is it just that the two should match in terms of order? Is there some way to run an ERC or have the equivalent of compiler warnings for spice?

Or am I failing to intuit that hooking up a RC network to the output of the Schmitt trigger would yield an identical triangle wave on both in and out?

As mentioned previously, while I have used spice simulators at Uni (multisim and LTSpice) there has been zero formal instruction in spice itself. Does anyone have any recommended reading on the topic? Other than the ngspice manual I suppose?

@jmk The plan is definitely to pivot to the 2R-1C style oscillator. I just wanted to be sure I could get the simplest implementation working with the simulator first :stuck_out_tongue:. Bad for momentum but this is as much a learning exercise for me as trying to build myself an oscillator.

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It wasn’t obvious how to re-use the same model for different units of the same symbol. Thanks for providing an example:

Sounds like this oscillator was not a cause for relaxation. I never understood why it is called a relaxation oscillator.

If you are driving and you hear the sound of a variable frequency oscillator in the siren of an emergency vehicle behind you, does that cause you to relax?

It’s from physics: Relaxation (physics) - Wikipedia

The equilibrium of the circuit is not related to your equilibrium. :wink:

Eyyy, this project ended up getting backburned due to school on my end.
Glad the thread ended up being helpful for someone else : )

Well OK thanks I learned something. But, I do not see that anything in the circuit is returning to equilibrium.

Actually I would think that description might better fit an oscillator used to demagnetize some iron (for example) by taking the magnetic state around a decaying BH curve.